Radial projection: A feature extraction method for topographical shapes

Abstract

Topographical images such as aerial and satellite images are usually similar with respect to colors and textures but not in shapes. Thus shape features of the images and the methods of extracting them become critical for effective image retrieval from topographical image databases. In this paper, we propose a shape feature extraction method as well as a similarity function for topographical image retrieval. The method extracts a set of attributes which can model the presence of holes and disconnected regions in images and is tolerant to pre-processing, more specifically segmentation, errors. Experiments suggest that retrieval using attributes extracted using the proposed method performs better than using the Curvature Scale Space (CSS) which is a well known method in the area of shape feature extraction. © Springer-Verlag Berlin Heidelberg 2005.